In the absence of very tight monitoring, and in light of Iranīs
increasing mastery over limited centrifuge technology, permitting the
country to continue enriching uranium at any level would still give
it the option of developing nuclear weapons.

With talks between
the P5+1 (the United States, Russia, China,
Britain, France, and Germany) and Iran set to resume in Istanbul on
April 13, officials are discussing possible compromises that might
persuade Tehran to give up any ambition of developing nuclear
weapons. Apparently, one of the principal components of these
proposals is acceptance of Iranīs right to enrich uranium to around
3.5%, a level suitable for civilian power reactors. But this could
turn out to be a fatal bargain: centrifuge technology is easy to
hide, and there are few barriers to continuing enrichment up to 90%,
the level needed for an atomic bomb.

BUYING LITTLE
TIME

Natural uranium contains just 0.7% of the fissile isotope U-
235,
which is the key to both controlled chain reactions in nuclear power
plants and uncontrolled, explosive chain reactions in atomic bombs.
Enriching this material is a progressively easier process. For
example, if the aim is to produce 90% enriched uranium, reaching the
3.5% level requires some 75% of the work. By the time 20% enrichment
is reached -- the level Iran currently achieves -- 90% of the work
has been done. Therefore, cutting a deal in which Iran gives up
enriching to 20% but continues enriching to 3.5% would buy relatively
little time. Worse, it would not solve the more fundamental problem:
the unknown scope and nature of Iranīs nuclear program.

In 1943,
when the United States was trying to enrich uranium to make
a bomb, it used two different methods. One scheme, based on magnets
called calutrons, used huge amounts of electricity and employed more
than 10,000 people. The other, using diffusion through specially made
barriers, was housed in the largest building ever constructed. The
beauty of the centrifuge method, used in Europe to fuel civilian
nuclear power plants since the 1970s, is that it requires much less:
a building the size of a supermarket and electricity equivalent to a
small industrial plant. The danger is that the same technology, when
mastered, can easily make the high-enriched uranium (HEU) needed for
nuclear explosives. And the building where this is being done can be
difficult to detect, as evidenced by North Koreaīs surprise 2010
revelation that it had built a centrifuge plant in its Yongbyon
nuclear complex, and Iranīs 2009 admission of work on a new facility
at Fordow.

IRANīS CENTRIFUGES

Currently, Iranīs
capabilities appear limited because of operational
problems with its IR-1 centrifuge, based on a design received from
Pakistan but originally developed in Europe. The IR-1 is prone to
breaking down, and Tehranīs efforts to develop more advanced models
have been hampered by international restrictions on its ability to
import the requisite high-strength steel, carbon fiber, aluminum, and
other components and machine tools.

Nevertheless, Iran has built
a formidable number of IR-1s and has
succeeded in enriching uranium to around 20%. Tehran claims it has
enriched to only 19.75%, thereby avoiding the 20% level, which is
notionally the divide between low-enriched uranium and HEU (so
designated because it is theoretically possible to make a nuclear
explosive using 20% enriched uranium, though such a device would be
so bulky and otherwise impractical that it would hardly qualify as a
bomb).

Originally, the governmentīs enrichment activities were
confined to
the giant facility at Natanz in central Iran. Recently, however, the
higher-enrichment centrifuge cascades were transferred to Fordow near
the holy city of Qom. This new facility was built under a mountain so
as to be immune from attack. Tehran has publicly stated that it plans
to build ten such facilities, so other locations may already be
designated or even under construction. Similarly, Pakistan -- the
source of Iranīs technology -- began with a main centrifuge plant at
Kahuta, then built a second facility at Gadwal, housed in one
building on the grounds of a huge munitions factory near Islamabad.
Pakistan also has one or more small centrifuge plants hidden in
mountain tunnels.

Without a diplomatic breakthrough, Iran would
likely be able to
produce weapons-grade HEU eventually despite the IR-1īs limitations,
since even inefficient centrifuges seem capable of success given
enough time. Although many Western experts sneer at the IR-1īs poor
performance, some estimate that Iran could make enough HEU for a bomb
perhaps later this year or in 2013. If Iran chose the breakout path,
it could conceivably make several bombsī worth of HEU within a matter
of a few weeks or months, depending on the number of centrifuges
deployed.

STRICTER SAFEGUARDS AND MORE OPENNESS

The
compromises that will be considered in Istanbul likely include
tight safeguard arrangements to prevent undisclosed Iranian
activities and/or the diversion of nuclear material, as well as
inspection of any suspicious sites. But a more immediate challenge is
for Tehran to answer existing questions about suspect activities that
suggest it has, at least in the past, worked on nuclear weapons
designs and breached its obligations under the Nuclear
Nonproliferation Treaty. This is a fundamental part of restoring
international confidence in the peaceful scope of Iranīs nuclear
program, in both the immediate and long term. Without this more
complete sort of understanding, the reputation and work of the
International Atomic Energy Agency (IAEA) would be fundamentally
undermined.

Throughout past discussions, Iran has repeatedly
offered "transparency" to build international confidence in its
activities. Thus, the first step going forward should be to secure a
clear commitment by competent Iranian authorities to full openness
and cooperation with the IAEA. Tehran must fully implement its
obligations under the IAEA statutes and Safeguards Agreement. It must
also return to provisional implementation of the Additional Protocol,
which strengthens inspection regimes, and work toward early
ratification of that protocol. In addition, it must provide all
necessary access and cooperation as the IAEA verifies the correctness
and completeness of its declaration.

Restraining Iranīs
enrichment activities might also involve limiting
its number of operational centrifuges from around 10,000 to just
1,000 -- a figure commensurate with estimates of the countryīs
maximum conceivable need for enriched uranium. In reality, though,
Iran has no need to make enriched uranium at all -- the fuel for its
Bushehr power reactor is supplied by Russia, and the fuel rods in the
Tehran Research Reactor (used to produce medical isotopes) could be
supplied from abroad if Tehran permitted it. In the past, Iran has
explained its activities by speaking of elaborate plans to become a
global supplier of enriched uranium for nuclear power stations. It
could try this gambit once again in Istanbul or later
talks.

CONCLUSION

Even if the parties make some diplomatic
progress at the Istanbul
summit, they are unlikely to build much trust. Yet such confidence
building -- which includes an even stricter safeguards regime -- is
essential if compromise is to work. In the absence of progress, Iran
could be tempted to pursue clandestine programs. And in the meantime,
its centrifuge skills and ability to produce enough high-enriched
uranium for a small arsenal of bombs are steadily increasing. (The
Washington Institute for Near East Policy Đ 2012 All rights reserved
04/12/12)